Method for extraction of paravallaridine and derivatives thereof



J. LE MEN 3,137,691 METHOD FOR EXTRACTION OF PARAVALLARIDINE AND DERIVATIVES THEREOF 1962 18 Sheets-Sheet 1 m: w 3 Q N t 9 m mm A. w W m N wmww m $2 mm a: 7 m l a 2: 2w 2 mfiw E 7 l a 5 www 8% m 88 an: S m 81 8% Q3 8m 3m 80 26 June 16, 1964 Filed Feb. 2,

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METHOD FOR EXTRACTION 0F PARAVALLARIDINE AND DERIVATIVES THEREOF Filed Feb. 2, 1962 18 Sheets-Sheet 2 a a \a m wh June 16, 1964 J. LE MEN 3,137,691

METHOD FOR EXTRACTION OF PARAVALLARIDINE AND DERIVATIVES THEREOF Filed Feb. 2, 1962 18 Sheets-Sheet 5 J1me 1964 J. LE MEN 3,137,691

METHOD FOR EXTRACTION OF PARAVALLARIDINE AND DERIVATIVES THEREOF Filed Feb. 2, 1962 18 Sheets-Sheet 4 June 16, 1964 J. LE MEN 3,137,691

METHOD FOR EXTRACTION OF PARAVALLARIDINE AND DERIVATIVES THEREOF Filed Feb. 2, 1962 18 Sheets-Sheet 5 June 16, 1964 J. LE MEN METHOD FOR EXTRACTION OF PARAVALLARIDINE AND DERIVATIVES THEREOF l8 Sheets-Sheet 6 Filed Feb. 2, 1962 new J. LE MEN METHOD FOR EXTRACTION OF PARAVALLARIDINE June 16, 1964 AND DERIVATIVES THEREOF l8 Sheets-Sheet 7 Filed Feb. 2, 1962 J. L METHOD FOR EXTRACTION OF PARAVALLARIDINE AND DERIVATIVES THEREOF June 16, 1964 E MEN 3,137,691

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METHOD FOR EXTRACTION OF FARAVALLARIDINE AND DERIVATIVES THEREOF Filed Feb. 2, 1962 18 Sheets-Sheet 9 Fig. II

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METHOD FOR EXTRACTION OF PARAVALLARIDINE AND DERIVATIVES THEREOF Filed Feb. 2, 1962 18 Sheets-Sheet 1O June 16, 1964 J. LE MEN METHOD FOR EXTRACTION OF PARAVALLARIDINE AND DERIVATIVES THEREOF l8 Sheets-Sheet 11 Filed Feb. 2, 1962 June 16, 1964 J. LE MEN METHOD FOR EXTRACTION OF PARAVALLARIDINE AND DERIVATIVES THEREOF 18 Sheets-Sheet 12 Filed Feb. 2, 1962 Q MN 3 m\ N\ R Q m b W In Q 3,137,691 ARI'DINE 18 Sheets-Sheet 13 June 16, 1964 J. LE MEN METHOD FOR EXTRACTIONv OF PARAVALL AND DERIVATIVES THEREOF Filed Feb. 2, 1962 3,137,691 INE l8 Sheets-Sheet 14 June 16, 1964 J. LE MEN METHOD FOR EXTRACTION OF PARAVALLARID AND DERIVATIVES THEREOF Filed Feb. 2, 1962 June 16, 1964 J. LE MEN 3,137,691

METHOD FOR EXTRACTION OF PARAVALLARIDINE AND DERIVATIVES THEREOF Filed Feb. 2, 1962 18 Sheets-Sheet l5 3 8w 3v 8 m 39 %Q 39w 8? 3; Q i Q E a E m w m 0 m M m Q 9m 3 mb m m mp1 aw QS June 16, 1964 J. LE MEN 3,137,691

METHOD FOR EXTRACTION OF PARAVALLARIDINE AND DERIVATIVES THEREOF Filed Feb. 2, 1962 18 Sheets-Sheet 16 n A a, Q 3

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June 16, 1964 Filed Feb. 2, 1962 J. LE MEN 3,137,691 METHOD FOR EXTRACTION OF PARAVALLARIDINE AND DERIVATIVES THEREOF 18 Sheets-Sheet 1'7 June 16, 1964 J. LE MEN 7 3,137,691

METHOD FOR EXTRACTION OF PARAVALLARIDINE AND DERIVATIVES THEREOF Filed Feb. 2, 1962 18 Sheets-Sheet l8 Fig. 29

United States PatentO 3,137,691 METHOD FOREXTRACTION F PARAVALLARI- DINE AND DERIVATIVES THEREOF Jean Le Men, Limeil- 'Brevannes, France, assignor to Roger Bellon, Neuilly-sur-Seine, France Filed Feb. 2, 1962, Ser. No. 170,569 Claims priority, application Great Britain Feb. 8, 1961 20 Claims. (Cl. 260-23957) This invention relates to new alkaloids, derivatives thereof and to processes for their preparation.

Cope'nding application No. 61,163 filed October 7-, 1960, describes and claims an alkaloid which is referred to as paravallarine, and is obtained from Paravallaris microphylla Pitard and hasv the following formula There are also described in this copending application various derivatives of this alkaloid, which are obtained either by substitution, or by opening of the lactone ring or by hydrogenation.

It has now been found that Paravallaris microp'hylla Pitard contains another alkaloid and the present invention is consequently concerned with a process for extracting this novel alkaloid and a process for preparing its derivatives; it is also concerned with the alkaloid itself and the derivatives of this alkaloid. I The new alkaloid, which is called paravallaridine, has an empirical formula of C H O N; and comprises three characteristic groups,..namely: a secondary amine group; a lactone group; an alcohol group. 7 g It also comprises a double bond which can be hydrogenated. The melting point of this alkaloid is 228 C. (Maquenne block); its infra-red spectrum is shown in curve 1 of the drawing accompanying the provisional specification. This spectrum, as well as the other spectra attached to the present application, have been established by means of a double-beam Baird apparatus using a suspension of the product in parafiin oil.

The rotary power of paravallaridine is (a) =52 (C=0.28 chloroform).

Having regard to the spectral similiarity between paravallaridine and the paravallarine which has already been described, and in view or a common botanical origin, it may be thought that the new alkaloid has a structure similar to that of paravallarine and it simply comprises one additional hydroxyl function. u 1

It could have been thought, therefore, that the formula of paravallaridine was as follows:

3,137,691 Patented June 16, 1964 2 Asa result of recent investigations, however, the ap- 'plicant has been able to show that the exact formula of the paravallaridine is as follows:

The experimental proofs of the accuracy of this formula are given below; i 5 Y J i (l) Paravallaridine has the same carbon "skeleton as paravalla'rine and the only difference existing between the two alkaloids is that the first. has a supernurrierary oxygerr atom engaged in the form of a hydroxyl (sec ondary alcohol function). i p v In order to establish this first conclusion, the alcohol group of the -mono-N-ace't'yl dihydro-paravallaridin, the compound-described below, has benconverted into a ketone group by means of the chr'oinic anhydride in aqueous acetic medium.-

The ketone obtained by this oxidation is C H' O4N and is also described below, and has been reduced ,by the Clernmensen method. It is thus formed of a derivative which is likewise described below (MP. 258. C. .(a) =l3.S (C=0.25 chloroform) of the formula C H O N; this derivative only differs from the N-acetyl dihydroparavallarine (C H O N) by the presence of a double bond inthe l5-16-position. i The N a'cetyl dihydroparavallarine has in eifect been obtained, as hereinafter described, by catalytic hydrogenation of the.N-acetyl-A -dihydrbparavallarine. I

In similar manner, the ketone, l6-oXo-N-methyl-dihydroparavallarine, resulting from the paravallaridine, has been reduced to form the unsaturated A derivative, which has been catalytically hydrogenated into N-methyl di hydroparayallarine.

Finally, the N-ethyl-A g-dihydroparavallarinol, resulting om the paravallaridine has been catalytically' hydro; geriated into N-etliyl dihydropa'ravallarinol. j

The reduction ofth'e ketone, 16-oXo-N-acetyl dihydrOE paravallarine by the Cleriimenseri method, would normally have had to. lead to the corresponding satu'ratjed'mono tleoxidised derivative,,th'at is to say, to th evN-iace'tyl dihydroparavallarine. In fact, the product which is obtained certainly has the same melting point and the same rotatory power as the N-acetyl dihydroparaval-larine, but it diliers in 'itsi nfra-re'dspectrum, essentially in the identiiication zone between 7 and 12g. By catalytichydro'g'enation, the product obtained, resulting from the origin of the paravallaridinmis converted into'a dihydtogen'atcd derivative,'the infra red spectrum of which can be strictly superimposed on that of the N acetyl dihyd'ropara'vab This triple identification enables it to 'be concluded absolutely that the paravallaridine has the same carbon skeleton as the paravallarine and that these womencules comprise,- in common? an N methylamino' group in the Zap-position, a double bond -at the 5-6-p'osition as and a lactone group at 18 20, but that the paravallaridine differs from the paravallarine by the presence of a secondary alcohol function in one position, the determination of which will hereinafter be proved.

The proof of the double bond at the -6-position results from the fact that the conversion of the paravallaridine derivatives to' the homologous derivatives of the dihydroparavallaridine is accompanied by a variation in the negative molecular rotation of the order of 100 (AM =M of the unsaturated derivative M of the hydrogenated derivative), as in the case of the converting of the paravallarine derivatives to those of the dihydroparavallarine.

(2) The supernumerary secondary alcohol group of the paravallaridine is in the 16-position.

The two ketones resulting from the chromic oxidation, either the N-acetyl dihydroparavallaridine or the N-rnethyl-dihydroparavallaridine, show in the infrared an absorption band C=O carbonyl, in part covered by the..C='O band of the 'y-lactone and situated at 5.7,ui

0.03 The position of this band is characteristic of the presence of a ketone function'on a ring having five elements( cyclopentanone). The result is that the ketone function of these derivatives is situated on the pentane D ring of the steroidskeleton, either in the IS-position or the 16-position. The IS-position is immediately excluded, since the formation of a 'ketone function in this position on a pregnane steroid skeleton causes a variation in the molecular' rotation in the positive direction of the order of +106 (according to Fieser and Fieser, Steroids, edition 1959, p. 179). On the other hand, the creation of a ketone in the 16-position is accompanied by a very negative variation in the molecular rotation (according to Klyne, The Chemistry of the Steroids, 1957 edition, p. 55).

The two ketones referred to above and hereinafter demicrophylla Pitard.

scribed respectively have the following specific rotatory powers 16:oXo-N-acety1 dihydroparavallarine: (oz) =247;

(C=0.2l, chloroform).

16-oxo-N-methyl dihydroparavallarine: (00 221 (C=0.l6, chloroform).

(3) The secondary alcohol group in the l6-position of the paravallaridine is oriented into a.

The easy'acetylation of the secondary alcohol group of the paravallaridine and correlatively the easy saponification of the resulting acetylated derivative are in favour molecular rotations.

The examination of the pairs of derivatives of the paravallaridine and of corresponding derivatives of paravallarine indicates that thecontribution of the hydroxyl group leads to a variation" of the order of to -90; According to D. K. Fukushima and T. F. Gallorghert]. Amer. Chem. Soc. 1951,.73, 1960), the variation due to the presence of hydroxyl is 60, when this hydroxyl is orientated into 160:.

Thus, both the chemical arguments and the physical arguments contribute to proving thatthe hydroxyl func tion of the paravallaridine fixed at the l6-position is oriented 'intof x. 7 1

The structure of theparavallaridine is thus proved and this compoundltherefore has the following nomenclature: 20s) 3/3N lactone 20 )-pregna-$-ene.

methylamino 160:,20 dihydroxyl 18 oic vallaridine formula.

This compound has arr-empirical formula of its melting point is 200 C. (Maquenne block); its rota tory power is (a) =49 (C=0.29 chloroform) and its infra-red spectrum is given in curve 2 of the accompanying drawing. i

The diacetylated derivative of paravallaridine has also been prepared, and the formula thereof is:

This derivative corresponds to the scientific name (208) 3BN methyl N acetylamino 16a acetoxy- ZO-hydroxy-l8-oic-lactone (+20)-pregna-5-ene.

a The melting point of this compound is. 240 C.;its

rotatory power is (a) =-36; (C=0.45 chloroform);

Curve 3 of the accompanying drawing'shows the infrared spectrum of this compound, which is character-ised on the one hand by an N-acetyl band at 6.1 microns and on the other hand by an'O-acetyl band at 5.72 microns.

The mono N-acetylated derivative of the paravallaridine has likewise been obtained, and in this derivative the hydrogen of the amine function of the paravallaridine is substituted byan acetyl radical; this compound which has the name of (20S)-3flN-methyl-N-acetylamino-16d;

20 dihydroxy 18 oic lactone 20) pregna S-ene, has the empirical formula C 4H O N and its melting point is 261 C. (block). Its infra-red spectrum is shown in curve 4 of the accompanying drawing.

By treating the paravallaridine or its derivatives with the object of opening the lactone function, two new alco'-' hol functions have been'obtained, as has been described in the copending applicationreferred to above. i Starting from the N-methyl-paravallaridine, it has been possible to obtain a triol havingthe, following formula:

H2 H0 CH l/ this compound conforming the name of (20S)-3,B-dimethylamino-l ,18,ZO-trihydrdxy-pregna-S-ene.

The melting point of this compound is 260 C. and its infra-red spectrum is shown in curve 5 of the accompanying drawing. a l

There have moreover been" obtained a certain numberof substituted derivatives of paravallaridine, the existence of which has further confirmed the accuracy of the para 

1. A COMPOUND OF THE FORMULA:
 19. A PROCESS FOR THE PREPARATION OF ALKALOIDS OF THE PARAVALIARINE SERIES WHICH COMPRISES CRUSHING A PLANT MATERIAL SELECTED FROM THE GROUP CONSISTING OF: THE LEAVES, STALKS AND ROOTS OF THE PLANT PARAVALLARIS MICROPHYLLA PITARD; REDUCING THE CRUSHED, MATERIAL TO POWDER; MIXING THE POWDER WITH AN AQUEOUS AMMONIA SOLUTION TO MAKE THE PH VALUE OF THE RESULTING MIXTURE HIGHER THAN 7; EXTRACTING THE MIXTURE WITH A WATER IMMISCIBLE, HYDROXYL GROUP-FREE SOLVENT, WHEREBY THE BASE ALKALOIDS ORIGINALLY CONTAINED IN THE PLANT MATERIAL ARE COLLECTED IN THE ORGANIC SOLVENT. 